Figure 3-1.—Sections of a CPU.
processing results in the OUTPUT STORAGE AREA.
From there the processing results can be transferred to
an output device. The fourth storage section, the
PROGRAM STORAGE AREA, contains the program
statements transferred from an input device to process
the data. Please note that the four areas (input, working
storage, output, and program storage) are NOT fmed in
size or location but are determined by individual
program requirements.
Output Unit
As program statements and data are received by the
CPU from an input device, the results of the processed
data are sent from the CPU to an OUTPUT DEVICE.
These results are transferred from the output storage
area onto an output medium, such as a floppy disk, hard
drive, video display, printer, and so on.
By now, you should have an idea of the functions
performed by a CPU. It is the CPU that executes stored
programs and does all of the processing and
manipulating of data. The input and output (I/O)
devices simply aid the computer by sending and
receiving data and programs.
COMPUTER SYSTEM HARDWARE
Computer system hardware includes the CPU and
its associated input and output devices. Input and
output devices, separate from the CPU itself, are called
peripheral equipment. The CPU communicates with
each peripheral device through input and output
channels. To operate an electronic-imaging
workstation, you must have a general understanding of
CPU primary and secondary storage, peripheral
devices, input and output channels, and modems.
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